300,000-year-old skulls found in Morocco shake the foundations of human origin theories

In June 2017, An international team of scientists unearthed teeth, bones and skulls belonging to three Homo sapiens adults, a teenager and a child among animal bones and stone tools in Morocco.

This discovery has pushed back the date of the origin of our species by
100,000 years as the oldest fossils of Homo sapiens before this
discovery are about 200,000 years old and were found in East Africa.

Credit : Shannon McPherron, MPI EVA Leipzig

Dating of the tools indicates the individuals were between 281,000 and 349,000 years old, the scientists report in two papers published in Nature today in June 2017.

Credit : Shannon McPherron, MPI EVA Leipzig

“My reaction was a big ‘wow’,” said Jean-Jacques Hublin, a senior scientist on the team at the Max Planck Institute for Evolutionary Anthropology in Leipzig. “I was expecting them to be old, but not that old.”

“This gives us a completely different picture of the evolution of our species. It goes much further back in time, but also the very process of evolution is different to what we thought,” Hublin told the Guardian. “It looks like our species was already present probably all over Africa by 300,000 years ago. If there was a Garden of Eden, it might have been the size of the continent.”

The fossils were excavated at a site called Jebel Irhoud, where similar fossils were unearthed in the 1960s and assigned an age of 40,000 years.

Since 2004, Dr. Hublin and his colleagues have been working through layers of rocks on a desert hillside at Jebel Irhoud. They have found a wealth of fossils, including skull bones from five individuals who all died around the same time.

Just as important, the scientists discovered flint blades in the same sedimentary layer as the skulls. The people of Jebel Irhoud most likely made them for many purposes, putting some on wooden handles to fashion spears.

Dr. Hublin and his colleagues used a method called thermoluminescence to calculate how much time had passed since the blades were burned. They estimated that the blades were roughly 300,000 years old. The skulls, discovered in the same rock layer, must have been the same age.

The first almost complete adult mandible discovered at the site of Jebel Irhoud. Credit: Jean-Jacques Hublin, MPI-EVA, Leipzig

When Hublin peered into the cavernous eye sockets of one of the skulls, he was astonished.

Instead of the robust features he was accustomed to seeing on the faces of an ancient human ancestor like Homo erectus or Homo heidelbergensis , this face bore a striking resemblance to his own.

"The face of these people is really a face that falls right in the middle of the modern variation," said Hublin. "They had a skull that is more elongated than most of us, but I'm not sure these people would stand out from a crowd today."

Credit : MPI EVA Leipzig

This unique combination of advanced and archaic features suggests something profound, Hublin said - he's convinced the Moroccan specimens "represent the very root of our species."

Modern humankind “wasn’t a new model of an automobile that appeared in a showroom with all the bells and whistles,” says Wood. “Different parts of modern human morphology and behavior probably came incrementally.”